Wyniki wyszukiwania - BazTech

1

Dynamic control of discharge energy during wedm for the purpose of eliminating vibrations of the wire tool electrode

Straka Ľuboslav, Kuchta Patrik

Management Systems in Production Engineering

|

2021

|

nr 4 (29)

260--265

EN

Production in all industry fields is currently affected by new scientific and technical knowledge and the requirements for its rapid deployment. In many cases, the most modern and highly sophisticated technical systems are applied. Simultaneously, fully automated production systems are rather successfully used and progressive production technologies are implemented. In most cases, there is an integral part of a management system that operates the challenging technological processes. These processes would not be executable without the system's precise control, which provides a suitable precondition for ensuring the high quality of manufactured products. However, the customer's demanding requirements are not always met. These involve increased requests for the quality of the final product due to the reduction of the tolerance band and application of high-strength materials. This paper aims to describe one of the solutions by which it is possible to achieve a higher quality of the machined surface after wire electrical discharge machining (WEDM). The solution proposes that through dynamic management, the WEDM process eliminates the vibrations of the wire tool electrode and thereby achieves a substantial increase in the quality of the eroded area in terms of its geometric accuracy. With the support of an extensive database of information with precise exchange of information, the proposed system will allow to control the electro discharge process with regard to the optimal way of operation of the electro discharge machine on the basis of individually selected conditions.

2

Trajectory tracking of a wheeled mobile robot with uncertainties and disturbances: proposed adaptive neural control

Martins N. A., Alencar M., Lombardi W. C., Bertol D. W., Pieri E. R., Filho H. F.

Control and Cybernetics

|

2015

|

Vol. 44, no. 1

47--98

EN

This paper analyses a trajectory tracking control problem for a wheeled mobile robot, Rusing integration of a kinematic neural controller (KNC) and a torque neural controller (TNC), in which both the kinematic and dynamic models contain uncertainties and disturbances. The proposed adaptive neural controller (PANC) is composed of the KNC and the TNC and is designed with use of a modeling technique of Gaussian radial basis function neural networks (RBFNNs). The KNC is a variable structure controller, based on the sliding mode theory and is applied to compensate for the disturbances of the wheeled mobile robot kinematics. The TNC is an inertia-based controller composed of a dynamic neural controller (DNC) and a robust neural compensator (RNC) applied to compensate for the wheeled mobile robot dynamics, bounded unknown disturbances, and neural network modeling errors. To minimize the problems found in practical implementations of the classical variable structure controllers (VSC) and sliding mode controllers (SMC), and to eliminate the chattering phenomenon, the nonlinear and continuous KNC and RNC of the TNC are applied in lieu of the discontinuous components of the control signals that are present in classical forms. Additionally, the PANC neither requires the knowledge of the wheeled mobile robot kinematics and dynamics nor the timeconsuming training process. Stability analysis, convergence of the tracking errors to zero, and the learning algorithms for the weights are guaranteed based on the Lyapunov method. Simulation results are provided to demonstrate the eﬀectiveness of the proposed approach.

3

Operating Results of Godfellow EFSOP at Riva, Verona, Italy

Pozzi M., Maiolo J., Scipolo V., Masoero D., Veneri N.

Archives of Metallurgy and Materials

|

2008

|

Vol. 53, iss. 2

443-450

EN

Tenova, formerly Techint Technologies, is a leading world-wide supplier of advanced technologies, products and services for the metal and mining industries. Tenova Goodfellow Inc. (TGI), formerly Techint Goodfellow Technologies Inc., has developed the Goodfellow Expert Furnace System Optimization Process (EFSOP ), which uses continuous extraction and analysis of EAF off-gases to dynamically optimize the chemical energy usage within the furnace. The benefits of the Goodfellow EFSOP system are increased process knowledge, lower conversion costs, and increased productivity. In November 2005, Tenova installed and commissioned two state-of-the-art Goodfellow EFSOP systems for RIVA ACCIAIO S.p.A. for their Verona meltshop. This dual system installation represented the first Goodfellow EFSOP installation in the Italian market. These new systems were installed on each of the two 80 ton Tenova EAFs at RIVA, Verona plant and incorporated continuous off-gas based closed-loop process control. Process analysis of the furnace operation commenced immediately after installation and commissioning of the EFSOP system. Ultimately process optimization included changes to the carbon/oxygen and methane practice, fume system adjustments, electrical practice adjustments and closed-loop control of oxygen, methane and injected carbon. This paper outlines the path to EAF optimization and the benefits achieved at RIVA, Verona by using the Goodfellow EFSOP system.

PL

Tenova, dawniej Technit Technologies, jest wiodącym światowym dostawcą wysoko rozwiniętych technologii, produktów i usług dla przemysłu metalowego i górniczego. W Tenova Goodfellow Inc. (TGI), przedtem Techint Goodfellow Technologies Inc. rozwinięto ekspertowy system optymalizacji procesu piecowego EFSOP, w którym wykorzystywana jest ciągła analiza gazów wylotowych z pieca łukowego do dynamicznej optymalizacji energii użytej w procesie. Zaletami systemu Goodfellow EFSOP jest rosnąca wiedza o procesie, niższe koszty przystosowania systemu oraz zwiększona wydajność. W listopadzie 2005, Tenova zainstalowała i nadzorowała dwa aktualnie rozwijane systemy EFSOP w stalowni RIVA ACCIAIO S.p.A. w Weronie. Jest to pierwsze wdrożenie na rynku włoskim. Systemy te zostały zainstalowane na dwóch 80 Mg piecach łukowych w zakładzie RIVA w Weronie i sterują procesem w obwodzie zamkniętym w oparciu o gazy wylotowe. Analiza procesu rozpoczęła się natychmiast po instalacji i nadzorze systemu. Ostatecznie optymalizacja procesu zawiera zmiany do stosownej praktyki wdmuchiwania węgla, tlenu i metanu, regulację systemu odciągowego dla gazów, elektrycznego oraz sterowanie w obwodzie zamkniętym tlenem, metanem i wdmuchiwaniem węgla . W artykule przedstawiono zarys optymalizacji pieca łukowego i korzyści osiągnięte w przedsiębiorstwie RIVA, wynikające z zastosowania systemu Goodfellow EFSOP.

4

EAF post-combustion control by on-line laser-based off-gas measurement

Krassnig H. J., Kleimt B., Voj L., Antrekowitsch H.

Archives of Metallurgy and Materials

|

2008

|

Vol. 53, iss. 2

455-462

EN

At the steel and rolling mill Marienh¨utte Graz the laser-based off-gas analysis system LINDARC R is installed just behind the gap of the 36 t EAF. High reliability and low response time of the system have been proven. The in-situ measured off-gas compounds in the combustion zone are CO and O2, as well as the off-gas temperature. To post-combust the evolved CO and H2 during the melt down period, four PC-lances are installed tangentially at the upper furnace shell (freeboard). A measurement campaign with an additional extractive IR/VIS off-gas analysis system has been performed, to acquire information on the off-gas flow rate and off-gas components including H2, CO2 and CH4, which can not be measured by the laser system, but are important for dynamic control and energy balance calculations. A dynamic closed loop control strategy of the post-combustion injectors based on the laser-based off-gas analysis system was developed and tested successfully. Post-Combustion oxy-gen is injected only if required due to high levels of CO in the off-gas, which increased its energetic efficiency dramatically. The trials were evaluated regarding the total energetic behaviour and the achieved savings by using of energy balance model calculations.

PL

Wstalowni i walcowni huty Marienh¨utte Graz system analizy gazów wylotowych w oparciu o pomiar laserowy LINDARC R jest zainstalowany tuż przy wylocie 36 Mg pieca łukowego. Udowodniona została duża wiarygodność i krótki czas odpowiedzi systemu. W strefie palenia następuje pomiar in-situ zawartości CO i O2 w mieszaninie gazów wylotowych oraz mierzona jest temperatura gazu. Do pomiaru CO i H2 podczas trwania wytopu po zapłonie, zainstalowane są stycznie cztery lance PC w górnej części pieca. Pomiary z dodatkowymi analizami IR/VIS gazów wylotowych zostały wykonane, aby zdobyć informacje o szybkości przepływu gazów i jego składzie z uwzględnieniem H2, CO2 i CH4, które nie mogą być mierzone za pomocą lasera, ale są konieczne do sterowania dynamicznego i obliczenia bilansu energii. Dynamiczne sterowanie obwodem zamkniętym inżektorów oparte na systemie analizy gazów wylotowych za pomocą lasera zostało z sukcesem rozwinięte i przetestowane. Tlen po zapłonie jest wdmuchiwany, jeżeli jest wysoki poziom CO w gazie wylotowym, co powoduje wzrost wydajności energetycznej. Próby zostały oszacowane na podstawie zachowania energetycznego i osiągniętych oszczędności przez użycie obliczeń modelowych bilansu energii.